I see your lights a little too far from the canopy maybe you can lower it, check if the dose of fertilizer is ok and you can expect a little yellowing of the leaves due flowering, how are they flowering?
I think its your lightning, You can use more warm light the yellow cfl and move closer to the plants the buds will become thicker with more light dont you forget that light from cfls fades faster than HID and also check the fert you are using it should be a flowering fert with more phosphorous.